The present invention relates to a re-usable envelope.
Re-usable envelopes are generally envelopes of, for example, a plastics material which may be used many times between, for example, different branches of the same business. The advantage of them is that, although initially more expensive than paper or manilla envelopes, they can be used a number of times and the cost of the envelope is very rapidly recouped.
Such re-usable envelopes often have a closure means in the form, for example of a zip closure. It is conventional to provide some kind of sealing device for maintaining the zip closed by holding the tag of the zip in the position in which the zip is closed.
Such sealing devices are normally in two parts, one part being expendable and the other part being retainable for re-use and attached to the envelope. Difficulties have arisen in maintaining the locking part, that is the tag of the zip, in position whilst the expendable part of the seal is inserted into the retained part of the seal.